1. Field of the Invention
The invention relates generally to communication systems and more specifically relates to methods and systems for communicating among communication devices identified by physical location and/or relative proximity.
2. Statement of the Problem
Numerous types of communication systems are known, commercially available and particularly suited to one or another particular application. For example, standard “landline” telephony networks permit a user to establish communications through a vast switched network to virtually any other point on the globe having similar landline communication systems. Or, for example, cellular telephony utilizes frequency transceivers and related protocols to couple an end user's cellular telephone to a nearby cellular tower. Cellular tower base stations forward digitized voice data, analog voice data or other digital data to other towers as a cell phone moves out of range and also forwards user data for coupling to standard landline based switched telephony systems. Thus cellular telephone users may connect with any landline telephone equipment or other cellular telephone users (coupled, in turn, to landline switched telephone networks through respective cell tower base stations).
In general, all such telephony communication systems are limited in two important respects. First, end user devices may communicate with one another only via a centralized server or network system (e.g., via respective cellular base stations and/or switched telephony networks). Landline telephony systems provide a network of switching devices to establish circuits between two or more end user telephone devices (or other data or voice communication devices). Cellular base stations atop cellular towers are required for cellular telephone users to establish connections with land based telephony systems or other cellular telephone users. If these centralized servers or networks are for any reason unavailable, no communication may be established between end users of the communication devices.
Secondly, to establish a call connection between two end user devices, a telephone number or other indicia (e.g., network address, ID, etc.) must be supplied to identify the other device with which communications are to be established. This indicia is static regardless of where the user is located and is required information to establish a call connection.
Radio frequency based communication systems such as citizens band (“CB”) radios. or simple “walkie talkie” radio devices do not require a centralized server or communication node but rather communicate directly from one end user's radio device to other user radio devices. However, radio communication systems do not generally provided for establishing a specific point-to-point call between one end user radio device and one or more particular, identified other end user radio devices. Rather, radio communication systems generally operate in a broadcast mode such that all users whose transceivers tuned to a particular frequency or channel receive every transmission on that frequency or “channel”. No private communication links may be established under such typical radio based communication systems. Although transmissions may be encrypted or scrambled, any radio device equipped with the proper decryption code and within transmission range can receive and decrypt the transmissions. No specific user or device may be identified in typical radio frequency based communication systems. Further, radio based communication systems generally do not provide for any protocol to establish the beginning of a call connection and the termination of an established connection. Radio communications are merely established by beginning transmission of a broadcast signal and ended when a user chooses to cease termination. Another weakness of radio based communication systems arises in that user data (voice or other data) is not encoded for spread spectrum high speed communications.
In a number of communication applications, it may be desirable or required to ensure continued communication capabilities without having to rely on a centralized server/network or communication tower. In an emergency scene response communication application or in a military combat communication application, it is important that the communication systems operate despite loss or failure of a central server/network or cell tower base stations. A communication system based on a centralized server/network or a cellular base station tower may be easily disabled by eliminating the central server or tower.
Further, it may be beneficial in many communication applications to permit establishment of a call connection (initiation of a call) to a specific device identified based on its geographical location (i.e., its physical proximity to the initiator of the call). Still further, in addition to location attributes to identify another communication device, it may be useful to identify a desired device for communication based upon other attributes of the user or the communication device.
For example, in a military context, it may be useful for military personnel in combat to be able to communicate with another soldier or other personnel based upon physical proximity to the initiator of the call. In other words, call “the closest reinforcements”. There may be no simple way to identify a phone number or other identifying address for the “nearest” personnel. Or, for example, it may be beneficial to initiate a call to the nearest personnel having particular attribute capabilities. In other words, call the nearest “EMT” personnel or call the nearest soldiers “with heavy artillery” or call the nearest “medic”, etc. Presently known communication systems do not provide simple techniques for identifying such personnel or attributes of another communication device and do not provide mechanisms to directly set up communications with such identified devices.
Similarly, in another exemplary application of communication systems, first responders in a rescue or emergency operation such as fire fighters, emergency medical technicians, police, etc., may desire communication systems that locate the nearest personnel for assistance or the nearest personnel with particular capabilities. Similar to military applications as noted above, rescue or emergency operations in the context of a disaster such as earthquakes or the collapse of a building may be significantly hindered if a central server or communication tower is disabled by the disaster they seek to address.
It is evident from the above discussion that a need exists for an improved communication architecture providing mobility, reliability and location oriented identification of communication devices and users.